PLS HELP ASAP THANKS ILL GIVE BRAINLKEST PLS THANKS PLS

What are tissues? a groups of tissues that work together b basic units of structure and function c groups of cells that perform the same function d multiple organs that perform a major function

Is dna the same in every cell in the human body explain your answer

Astudy by solloch and et. al., in 2017, gives the map above which shows the frequency of alleles with a ccr5-delta32 mutations over 87 different countries. this mutation deletes the presence of a co-receptor (ccr5) on the outside of human t-cells (lymphocytes). some viruses, such as the one responsible for the black death and human immunodeficiency virus (hiv), require this receptor for attachment to host cells during the infection process. the black death was an epidemic that passed over northern europe during the 14th century killing nearly 60% of europeans. according to this information, which explanation best explains why northern europeans show a greater immunity for hiv than some other parts of the world?